JP2011215455A - Liquid crystal display device, method for manufacturing the same, and projection display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid crystal display device capable of further improving a light resistance life, a method for manufacturing the liquid crystal display device and a projection display device.SOLUTION: The liquid crystal display device includes an element substrate 11 and an opposing substrate which sandwich a liquid crystal layer 13. The element substrate 11 has a first dielectric layer 33 containing SiOand a first inorganic alignment film 34 formed on the first dielectric layer 33 by oblique evaporation to regulate the alignment of liquid crystal molecules that constitute the liquid crystal layer 13. A silanol group on the surface of the first dielectric layer 33 is surface-treated with a silane compound.

Description

  The present invention relates to a liquid crystal display device, a method for manufacturing the liquid crystal display device, and a projection display device.

In a liquid crystal display device, there is a vertical alignment mode in which liquid crystal molecules are aligned substantially perpendicularly to a substrate surface in a state where no voltage is applied, as an alignment mode of liquid crystal molecules that regulates alignment of liquid crystal molecules. Thus, in a liquid crystal display device including a liquid crystal having negative dielectric anisotropy, when aligning liquid crystal molecules, not only an organic alignment film formed of an organic material such as polyimide, but also SiO, SiO _2, etc. An inorganic alignment film formed by obliquely depositing an inorganic material on a substrate is also used.

  In recent years, with the increase in definition and brightness of liquid crystal projectors, the intensity of light incident on liquid crystal display devices used in liquid crystal projectors has increased. Therefore, in a liquid crystal display device using an organic alignment film, the alignment film is deteriorated by light or heat, and as a result, the alignment regulating force of the liquid crystal molecules by the alignment film is reduced and the alignment state of the liquid crystal molecules is disturbed. This may cause display defects such as a reduction in the contrast cost of the liquid crystal display device. Therefore, an inorganic alignment film that is superior in light resistance and heat resistance as compared to an organic alignment film has been attracting attention.

  However, silanol groups may be formed in the inorganic alignment film, for example, when moisture reacts. This silanol group may photochemically react with liquid crystal molecules by light generated during the operation of the liquid crystal display device and cause light leakage or the like in the liquid crystal display device. Therefore, a method for suppressing the photochemical reaction between the silanol group and the liquid crystal molecules by applying a surface treatment to the inorganic alignment film has been proposed (for example, see Patent Document 1).

JP 2007-25529 A JP 2007-25530 A

  However, the following problems remain in the conventional liquid crystal display device. That is, a dielectric layer that flattens the surface is formed on the pixel electrode that drives the liquid crystal layer in order to absorb the irregularities formed by the pixel electrode and prevent the alignment of liquid crystal molecules from being disturbed by the irregularities. An inorganic alignment film is formed on the dielectric layer, but there is a problem in that the light-resistant life may be reduced by forming the dielectric layer as compared with the case where the dielectric layer is not formed. is there.

  Accordingly, an object of the present invention is to provide a liquid crystal display device, a method for manufacturing the liquid crystal display device, and a projection display device that can further improve the light fastness life.

The present invention employs the following configuration in order to solve the above problems. That is, the liquid crystal display device according to the present invention is a liquid crystal display device including a pair of substrates sandwiching a liquid crystal layer, wherein at least one of the pair of substrates includes a dielectric layer containing SiO ₂ and the dielectric layer. And an inorganic alignment film that regulates the alignment of liquid crystal molecules constituting the liquid crystal layer, and the silanol group on the surface of the dielectric layer is surface-treated with a silane compound. It is characterized by being.

The method for manufacturing a liquid crystal display device according to the present invention is a method for manufacturing a liquid crystal display device including a pair of substrates that sandwich a liquid crystal layer, and the step of forming at least one of the pair of substrates is performed on a substrate. Dielectric layer forming step for forming a dielectric layer containing SiO _2, and alignment film forming step for forming an inorganic alignment film for regulating the alignment of liquid crystal molecules constituting the liquid crystal layer on the dielectric layer by oblique deposition And a surface treatment step of surface-treating silanol groups on the surface of the dielectric layer with a silane compound.

  In this invention, the surface of the dielectric layer exposed to the liquid crystal layer on the lower surface of the inorganic alignment film formed by oblique deposition is surface-treated, thereby reducing silanol groups that react with liquid crystal molecules on the surface of the dielectric layer. can do. That is, since the inorganic alignment film is formed by oblique deposition, the surface of the dielectric layer is not completely covered by the inorganic alignment film having a low density, and a part of the surface is exposed to the liquid crystal layer. Silanol groups remaining in the exposed portions may photochemically react with liquid crystal molecules. Therefore, by subjecting at least a portion of the dielectric layer exposed to the liquid crystal layer to surface treatment, it is possible to prevent deterioration of the liquid crystal layer and increase the light resistance life of the liquid crystal display.

In the liquid crystal display device according to the present invention, it is preferable that a surface treatment is not performed on a portion of the dielectric layer that is covered with a column that forms the inorganic alignment film.
In the method for manufacturing a liquid crystal display device according to the present invention, the surface treatment step is preferably performed after the alignment film forming step.
In the present invention, the surface treatment can be performed collectively on the inorganic alignment film and the surface of the dielectric layer exposed from the inorganic alignment film.

［式中ｎは１または２、ｍは６から１８の整数である］で表されることが好ましい。
この発明では、長鎖アルキルを有するシラン化合物を用いることによって無機配向膜と液晶層との間に強い界面アンカリング効果を発生させることができ、液晶分子の配向規制を行うことができる。 In the method for producing a liquid crystal display device according to the present invention, the silane compound is represented by the general formula (1).

[Wherein n is 1 or 2, and m is an integer of 6 to 18].
In the present invention, by using a silane compound having a long-chain alkyl, a strong interface anchoring effect can be generated between the inorganic alignment film and the liquid crystal layer, and the alignment of liquid crystal molecules can be regulated.

In the liquid crystal display device according to the present invention, it is preferable that a surface treatment is performed on a portion of the dielectric layer that is covered with a column constituting the inorganic alignment film.
In the method for manufacturing a liquid crystal display device according to the present invention, the surface treatment step is preferably performed before the alignment film forming step.
In the present invention, the silanol groups remaining on the surface of the dielectric layer can be more reliably reduced by performing the surface treatment only on the dielectric layer and not on the inorganic alignment film.

［式中ｎは１または２、ｍは６から１８の整数である］で表されることが好ましい。
この発明では、表面処理された部分が無機配向膜で覆われ、液晶層に対して露出する部分が少ないため、長鎖アルキルを有するシラン化合物に限らずさまざまなシラン化合物を用いることができる。 In the method for producing a liquid crystal display device according to the present invention, the silane compound is represented by the general formula (2).

[Wherein n is 1 or 2, and m is an integer of 6 to 18].
In this invention, since the surface-treated portion is covered with the inorganic alignment film and the portion exposed to the liquid crystal layer is small, various silane compounds can be used in addition to the silane compound having a long-chain alkyl.

In the liquid crystal display device according to the present invention, the surface of the column is preferably subjected to surface treatment.
Moreover, it is preferable that the manufacturing method of the liquid crystal display device in this invention surface-treats the surface of the said inorganic alignment film with a silane compound after the said alignment film formation process.
In the present invention, silanol groups that react with liquid crystal molecules on the surface of the inorganic alignment film can be reduced by performing the surface treatment again after forming the inorganic alignment film.

In the method for manufacturing a liquid crystal display device according to the present invention, it is preferable that in the dielectric layer forming step, the dielectric layer is formed by a plasma CVD method using tetraethoxysilane as a source gas.
In the present invention, residual cyanol groups on the surface of the dielectric layer can be reduced in advance.

A projection display device according to the present invention includes the above-described liquid crystal display device.
In the present invention, as described above, by reducing the silanol groups that react with the liquid crystal molecules on the surface of the dielectric layer, it is possible to prevent deterioration of the liquid crystal layer and increase the light resistance life of the liquid crystal display device.

1 is a schematic plan view showing a liquid crystal display device according to a first embodiment of the present invention. FIG. 2 is an equivalent circuit diagram of FIG. 1. It is sectional drawing which shows a pixel area. FIG. 4 is a partially enlarged view of FIG. 3. It is process drawing which shows the manufacturing method of the liquid crystal display device of FIG. It is explanatory drawing which shows surface treatment. It is a schematic block diagram which shows a projection type display apparatus provided with the liquid crystal display device of FIG. It is the elements on larger scale which show the liquid crystal display device in 2nd Embodiment. It is process drawing which shows the manufacturing method of the liquid crystal display device of FIG. It is the elements on larger scale which show the liquid crystal display device in 3rd Embodiment.

[First Embodiment]
Hereinafter, a liquid crystal display device and a liquid crystal display device manufacturing method according to a first embodiment of the present invention will be described with reference to the drawings. In each drawing used in the following description, the scale is appropriately changed to make each member a recognizable size.

[Liquid Crystal Display]
The liquid crystal display device 1 according to the present embodiment is a liquid crystal display device used as a light modulation unit in a projector (projection type display device) 100 described later, for example, and as shown in FIG. 1, an element substrate (first substrate) 11 is used. And a counter substrate (second substrate) 12 and a liquid crystal layer 13 sandwiched between the element substrate 11 and the counter substrate 12. Further, in the liquid crystal display device 1, the element substrate 11 and the counter substrate 12 are bonded together by a frame-shaped sealing material 14 provided on the outer peripheral portion of the facing region where the element substrate 11 and the counter substrate 12 face each other. An image display region is formed inside the sealing material in the liquid crystal display device 1.

  In the image display area of the liquid crystal display device 1, a plurality of pixel areas are arranged in a matrix as shown in FIG. In each of the pixel regions, a pixel electrode 21, a common electrode 43 described later, and a TFT element 22 for controlling the switching of the pixel electrode 21 are formed. In the image display area, a plurality of data lines 23 and scanning lines 24 are arranged in a grid pattern.

The TFT element 22 has a source connected to the data line 23, a gate connected to the scanning line 24, and a drain connected to the pixel electrode 21.
The data line 23 is configured such that image signals S1 to Sn are supplied to each pixel region from a data line driving circuit (not shown). Further, the scanning line 24 has a configuration in which scanning signals G1 to Gm are supplied to each of the sub-pixel regions from a scanning line driving circuit (not shown). Note that a storage capacitor 25 is provided in parallel with the pixel electrode 21 in order to prevent leakage of the image signals S <b> 1 to Sn written to the pixel electrode 21. Further, the liquid crystal display device 1 is formed with terminals (not shown) for connecting the data line driving circuit and the scanning line driving circuit to the outside of the liquid crystal display device 1.

Next, a detailed configuration of the liquid crystal display device 1 will be described.
As shown in FIG. 3, the element substrate 11 includes a substrate body 31, an element formation layer 32 formed on the inner surface (the liquid crystal layer 13 side) of the substrate body 31, and pixels formed on the element formation layer 32. The electrode 21, the first dielectric layer (dielectric layer) 33 formed on the pixel electrode 21, and the first inorganic alignment film (inorganic alignment film) formed on the liquid crystal layer 13 side of the first dielectric layer 33 34.
The element forming layer 32 has a structure in which an insulating film, a semiconductor film, and a conductor film are appropriately laminated, and constitutes the data line 23, the scanning line 24, and the TFT element 22, and pixel electrodes formed in each of a plurality of pixel regions. 21 can be driven individually. The substrate body 31 and the element forming layer 32 constitute a base body 35.
The pixel electrode 21 is formed of a conductive material constituting a reflective film such as Al.

The first dielectric layer 33, such as SiO _2, is formed of a dielectric containing SiO _2, it is formed on the substrate 35 by the plasma CVD method using for example tetraethoxysilane as raw material gases.
Similar to the first dielectric layer 33, the first inorganic alignment film 34 is formed of a dielectric containing SiO ₂ such as SiO ₂ , and as shown in FIG. It has a plurality of columns 34 a formed so as to be inclined with respect to the surface of the layer 33. Since the first inorganic alignment film 34 is formed by oblique vapor deposition, the column 34 a is formed on the surface of the first dielectric layer 33 in a low density state. Therefore, the surface of the first dielectric layer 33 is exposed from between the columns 34a.

  Also, triethoxydecylsilane represented by the following formula (3) was melted in a solvent on the surface of the first inorganic alignment film 34 and the surface of the first dielectric layer 33 exposed from between the columns 34a. Surface treatment using a silane compound solution is performed. By performing such surface treatment, a surface treatment film 36 is formed on the surface of the first inorganic alignment film 34 and the portion of the surface of the first dielectric layer 33 exposed from between the columns 34a. The alkyl group at is reduced.

On the other hand, the counter substrate 12 is formed on the light shielding film 42, a substrate body (base body) 41 made of a translucent material such as glass or quartz, a light shielding film 42 formed on the inner surface of the substrate body 41, and the like. Common electrode 43, second dielectric layer (dielectric layer) 44 formed on common electrode 43, and second inorganic alignment film (inorganic alignment) formed on liquid crystal layer 13 side of second dielectric layer 44. Film) 45.
The light shielding film 42 is made of, for example, black resin, and is formed in a region overlapping the edge of the pixel region in plan view on the surface of the substrate body 41, and borders the pixel region.

The common electrode 43 is made of a light-transmitting conductive material such as ITO or IZO. The common electrode 43 is an electrode that is common throughout the plurality of pixel regions.
The second dielectric layer 44, such as well such as SiO ₂ and the first dielectric layer 33 is formed of a dielectric containing SiO _2. The second dielectric layer 44 is formed on the substrate body 41 by a plasma CVD method using, for example, tetraethoxysilane as a source gas.

Similar to the first inorganic alignment film 34, the second inorganic alignment film 45 is formed of a dielectric containing SiO ₂ such as SiO ₂ and is applied to the surface of the second dielectric layer 44 by oblique vapor deposition. It is formed so as to be inclined. The surface of the second dielectric layer 44 is exposed from between the columns constituting the second inorganic alignment film 45.
Further, the second inorganic alignment film 45 is subjected to a surface treatment using a silane compound solution obtained by melting triethoxydecylsilane in a solvent, and the surface of the second inorganic alignment film 45 and the second dielectric layer 44 are treated. Alkyl groups on the exposed surface of the surface of the column are reduced.

  The liquid crystal layer 13 is formed of a liquid crystal having negative dielectric anisotropy whose refractive index anisotropy Δn is, for example, 0.1. Here, the first and second inorganic alignment films 34 and 45 provided on the element substrate 11 and the counter substrate 12, respectively, are formed by oblique deposition, so that the respective methods of the element substrate 11 and the counter substrate 12 are performed. A pretilt for tilting liquid crystal molecules by a predetermined angle from the line direction is given. In this embodiment, the azimuth direction of the pretilt between the element substrate 11 and the counter substrate 12 is set to be in an antiparallel (antiparallel) state. Therefore, the twist angle of the liquid crystal molecules is set to approximately 0 degrees in the initial alignment state where no voltage is applied.

[Manufacturing method of liquid crystal display device]
Next, a method for manufacturing the above-described liquid crystal display device 1 will be described.
First, a method for forming the element substrate 11 will be described. First, an element formation layer 32 is formed by appropriately stacking an insulating film, a semiconductor film, and a conductor film on the substrate body 31, and the pixel electrode 21 is formed on the element formation layer 32 (see FIG. 5A).

Then, a first dielectric layer 33 made of a dielectric containing SiO ₂ is formed on the element forming layer 32 by using a plasma CVD method using tetraethoxysilane as a source gas (dielectric layer forming step, FIG. b)). At this time, irregularities are formed on the surface of the first dielectric layer 33 by the pixel electrode 21 formed on the element forming layer 32, but the surface is planarized by chemical mechanical polishing (CMP) or etch back.

Subsequently, a first inorganic alignment film 34 made of SiO ₂ is formed on the surface of the first dielectric layer 33 by using oblique vapor deposition (alignment film forming step, see FIG. 5C). At this time, since the plurality of columns 34 a constituting the first inorganic alignment film 34 are formed by oblique deposition, the plurality of columns 34 a are formed on the first dielectric layer 33 in a low density state. Therefore, the surface of the first dielectric layer 33 is not completely covered by the column 34a constituting the first inorganic alignment film 34, and a part thereof is exposed (see FIG. 5D). Here, as shown in FIG. 6A, an alkyl group remains on a portion of the surface of the first dielectric layer 33 exposed from between the columns 34a.

Then, using a silane compound solution in which triethoxydecylsilane is melted in a solvent, surface treatment is performed on the exposed portion of the surface of the first inorganic alignment film 34 and the first dielectric layer 33 (surface treatment). Step, see FIG. 5 (e)). As a result, the surface of the first inorganic alignment film 34 and the surface of the first dielectric layer 33 exposed from between the columns 34a are covered with the surface treatment film 36, as shown in FIG. 6B. In addition, the remaining alkyl groups are reduced.
In this way, the element substrate 11 is formed.

Next, a method for forming the counter substrate 12 will be described. First, the light shielding film 42 and the common electrode 43 are formed on the substrate body 41, and the second dielectric made of a dielectric containing SiO ₂ is used on the common electrode 43 by plasma CVD using tetraethoxysilane as a source gas. The body layer 44 is formed (dielectric layer forming step).
In the same manner as described above, the second inorganic alignment film 45 made of SiO ₂ is formed on the surface of the common electrode 43 by using oblique deposition (alignment film forming step). Thereafter, a surface treatment is performed on the second inorganic alignment film 45 using a silane compound solution obtained by melting triethoxydecylsilane in a solvent (surface treatment step). Thereby, the alkyl group remaining on the surface of the second inorganic alignment film 45 is reduced.
In this way, the counter substrate 12 is formed.

  Thereafter, the element substrate 11 and the counter substrate 12 are bonded together with a sealing material in a state where the liquid crystal layer 13 is sandwiched between the element substrate 11 and the counter substrate 12. Here, since the surface treatment is performed on the first and second inorganic alignment films 34 and 43 using a silane compound solution in which triethoxydecylsilane having a long-chain alkyl is melted in a solvent, the first and second inorganic alignment films are provided. A strong interface anchoring effect is generated between the alignment films 34 and 43 and the liquid crystal layer 13 to regulate the alignment of liquid crystal molecules. The liquid crystal display device 1 is manufactured as described above.

[Projection type display device]
The liquid crystal display device 1 described above is used as a light modulation unit of the projector 100 as shown in FIG. As shown in FIG. 7, the projector 100 includes a light source 101, dichroic mirrors 102 and 103, a light modulating unit for red light 104, a light modulating unit for green light 105, and a blue light, each including the liquid crystal display device 1 of the present invention. A light modulator 106, a light guide 107, reflection mirrors 110 to 112, a cross dichroic prism 113, and a projection lens 114. The color image light emitted from the projector 100 is projected on the screen 115.

The light source 101 includes a lamp 101a such as a metal halide, and a reflector 101b that reflects light from the lamp 101a.
The dichroic mirror 102 is configured to transmit red light included in white light from the light source 101 and reflect green light and blue light. The dichroic mirror 103 is configured to transmit blue light and reflect green light among green light and blue light reflected by the dichroic mirror 102.

  The light modulation means 104 for red light is configured to receive red light transmitted through the dichroic mirror 102 and modulate the incident red light based on a predetermined image signal. Further, the green light light modulating means 105 is configured to receive the green light reflected by the dichroic mirror 103 and modulate the incident green light based on a predetermined image signal. The blue light light modulating means 106 is configured to receive the blue light transmitted through the dichroic mirror 103 and modulate the incident blue light based on a predetermined image signal.

The light guide unit 107 includes an incident lens 107a, a relay lens 107b, and an output lens 107c, and is provided to prevent light loss due to a long optical path of blue light.
The reflection mirror 110 is configured to reflect the red light transmitted through the dichroic mirror 102 toward the light modulation means 104 for red light. The reflection mirror 111 is configured to reflect the blue light transmitted through the dichroic mirror 103 and the incident lens 107a toward the relay lens 107b. The reflection mirror 112 is configured to reflect the blue light emitted from the relay lens 107b toward the emission lens 107c.

The cross dichroic prism 113 is formed by bonding four right-angle prisms, and a dielectric multilayer film reflecting red light and a dielectric multilayer film reflecting blue light are formed in an X shape at the interface. Has been. These dielectric multilayer films combine light of three colors to form light representing a color image.
The projection lens 114 is configured to enlarge and project the color image synthesized by the cross dichroic prism 113 onto the screen 115.

According to the liquid crystal display device 1 and the manufacturing method of the liquid crystal display device 1 and the projector 100 configured as described above, the first and second inorganic alignment films 34, among the surfaces of the first and second dielectric layers 33 and 43, By applying a surface treatment to the portion exposed from 43 to the liquid crystal layer 13, silanol groups that react with liquid crystal molecules on the surfaces of the first and second dielectric layers 33 and 43 can be reduced. Therefore, the deterioration of the liquid crystal layer 13 can be prevented more reliably, and the light resistance life of the liquid crystal display device 1 can be increased.
Here, by performing a surface treatment after the formation of the first inorganic alignment film 34, it is possible to collectively perform the surface treatment on each of the first inorganic alignment film 34 and the first dielectric layer 33. The same applies to the second inorganic alignment film 45 and the second dielectric layer 44. At this time, since the first and second inorganic alignment films 34 and 43 are subjected to surface treatment using a silane compound solution obtained by melting triethoxydecylsilane having a long chain alkyl in a solvent, the first and second dielectrics A strong interface anchoring effect is generated between the body layers 33 and 43 and the liquid crystal layer 13, and the alignment of liquid crystal molecules can be regulated.

  In this embodiment, surface treatment is performed using a silane compound solution in which triethoxydecylsilane is melted in a solvent, but trimethoxydecylsilane represented by the following formula (4) is melted in the solvent. Surface treatment may be performed using a silane compound solution.

[Second Embodiment]
Hereinafter, a liquid crystal display device according to a second embodiment of the present invention and a method for manufacturing the liquid crystal display device will be described with reference to the drawings. In this embodiment, since the manufacturing method of the element substrate and the counter substrate is different from that of the first embodiment, this point will be mainly described, and the constituent elements described in the above embodiment are denoted by the same reference numerals, The description is omitted.

[Liquid Crystal Display]
As shown in FIG. 8, the element substrate 201 of the liquid crystal display device 200 according to the present embodiment has a surface treatment film 202 formed by subjecting the first dielectric layer 33 to surface treatment. In this surface treatment, a silane compound solution obtained by melting triethoxymethylsilane represented by the following formula (5) in a solvent is used. In the present embodiment, the surface of the column 34a constituting the first inorganic alignment film 34 is not subjected to surface treatment, and the surface treatment film 202 is not formed.

  Although not shown, the same surface treatment is also applied to the counter substrate of the liquid crystal display device 200.

[Manufacturing method of liquid crystal display device]
Next, a method for manufacturing the liquid crystal display device 200 will be described. First, similarly to the above-described first embodiment, the element formation layer 32 and the pixel electrode 21 are formed on the substrate body 31, and the first dielectric layer 33 is further formed (dielectric layer formation step, FIG. a)).
Then, a surface treatment is performed on the surface of the first dielectric layer 33 using a silane compound solution obtained by melting triethoxymethylsilane in a solvent (a surface treatment step, see FIG. 9B). Thereby, the surface of the first dielectric layer 33 is covered with the surface treatment film 202, and the remaining alkyl groups are reduced.

Subsequently, a first inorganic alignment film 34 made of SiO ₂ is formed on the surface of the first dielectric layer 33 by using an oblique vapor deposition method (inorganic alignment film, see FIG. 9C). At this time, the plurality of columns 34 a constituting the first inorganic alignment film 34 are not covered with the surface treatment film 202.
In this way, the element substrate 201 is formed.
Thereafter, a counter substrate is formed in the same manner as the element substrate 201, and the liquid crystal display device 200 is manufactured in the same manner as in the first embodiment.

  The liquid crystal display device 200 configured as described above and the method for manufacturing the liquid crystal display device 200 also have the same operations and effects as described above. Silanol groups remaining on the surface of the body layer 33 can be more reliably reduced. In addition, since the surface treatment layer 202 is covered with the first inorganic alignment film 34 and the surface treatment layer 202 is not directly involved in the alignment regulation of liquid crystal, various silane compounds are used in addition to silane compounds having long-chain alkyl. it can.

[Third Embodiment]
Hereinafter, a third embodiment of a liquid crystal display device and a method of manufacturing the liquid crystal display device according to the present invention will be described with reference to the drawings. In this embodiment, since the silane compound used is different from that in the first embodiment, this point will be mainly described, and the same reference numerals are given to the components described in the above embodiment, and the description will be given. Omitted.

[Liquid Crystal Display]
In the element substrate 251 of the liquid crystal display device 250 according to the present embodiment, as shown in FIG. 10, a surface treatment film 252 is formed on the surface of the column 34 a constituting the first inorganic alignment film 34. In the surface treatment of the first inorganic alignment film 34, as in the first embodiment described above, a silane compound solution in which triethoxydecylsilane is melted in a solvent is used.
Although not shown, the same surface treatment is also applied to the counter substrate of the liquid crystal display device 250.

[Manufacturing method of liquid crystal display device]
Next, a method for manufacturing the liquid crystal display device 250 will be described. First, as in the second embodiment described above, the surface of the first dielectric layer 33 is subjected to a surface treatment using a silane compound in which triethoxymethylsilane is dissolved in a solvent, and then the first inorganic alignment film 34. Form. Then, the first inorganic alignment film 34 is subjected to a surface treatment using a silane compound solution in which triethoxydecylsilane is melted in a solvent. In this way, the element substrate 251 is formed.
Thereafter, a counter substrate is formed in the same manner as the element substrate 251, and the liquid crystal display device 250 is manufactured in the same manner as in the above-described embodiment.

  The liquid crystal display device 250 having the above configuration and the manufacturing method of the liquid crystal display device 250 also have the same operations and effects as described above. However, by performing the surface treatment again after forming the first inorganic alignment film 34, Silanol groups on the surface of the first inorganic alignment film 34 can be reduced.

In addition, this invention is not limited to the said embodiment, A various change can be added in the range which does not deviate from the meaning of this invention.
For example, although the silane compound used for the surface treatment mentions ethoxy (OC ₂ H ₅ ) as an alkoxy group, it may be another alkoxy group such as methoxy (OC ₁ H ₃ ) or as an alkyl group. Although methyl (C ₁ H ₃ ), hexyl (C ₆ H ₁₃ ) and decyl (C ₁₀ H ₂₁ ) are mentioned, other alkyl groups may be used. Furthermore, the silane compound used for the surface treatment is not limited to those listed in the general formula (1) and the general formula (2), but may be other silane compounds.
The liquid crystal display device is not limited to a reflective liquid crystal display device, and may be a transmissive or transflective liquid crystal display device.
Although the surface treatment is performed on the dielectric layers on both the element substrate and the counter substrate, it is sufficient that the surface treatment is performed on at least one of the element substrate and the counter substrate.
The dielectric layer may use a gas other than tetraethoxysilane as a source gas.
The liquid crystal layer is composed of liquid crystal molecules driven by the VA method, but may be composed of liquid crystal molecules driven by other methods such as a liquid crystal molecule driven by the NT (Twisted Nematic) method.

  The liquid crystal display device is not limited to a projection type display device such as a projector, and may be used for a direct-view type display device such as a mobile phone. Accordingly, the electronic apparatus including the liquid crystal display device is not limited to a projection display device such as a projector, but is a mobile phone, a PDA (personal digital assistant), a handy terminal, an electronic book, a notebook personal computer, a personal computer, a digital still Various electronic devices such as a camera, a liquid crystal television, a viewfinder type or a monitor direct-view type video tape recorder, a car navigation device, a pager, an electronic notebook, a calculator, a word processor, a workstation, a videophone, and a POS terminal may be used.

1,200,250 Liquid crystal display device, 11,201,251 Element substrate (substrate), 12 Counter substrate (substrate), 13 Liquid crystal layer, 33 First dielectric layer (dielectric layer), 34 First inorganic alignment film ( Inorganic alignment film), 34a column, 41 substrate body (base), 44 second dielectric layer (dielectric layer), 45 second inorganic alignment film (inorganic alignment film), 100 projector (projection display), 104 red Light modulation means for light (liquid crystal display device), 105 Light modulation means for green light (liquid crystal display device), 106 Light modulation means for blue light (liquid crystal display device)

Claims (12)

A liquid crystal display device comprising a pair of substrates sandwiching a liquid crystal layer,
At least one of the pair of substrates includes a dielectric layer containing SiO ₂ and an inorganic alignment film that is formed on the dielectric layer by oblique vapor deposition and regulates the alignment of liquid crystal molecules that constitute the liquid crystal layer. Have
A liquid crystal display device, wherein a silanol group on the surface of the dielectric layer is surface-treated with a silane compound.   2. The liquid crystal display device according to claim 1, wherein a surface treatment is not performed on a portion of the dielectric layer that is covered with a column constituting the inorganic alignment film.   The liquid crystal display device according to claim 1, wherein a surface treatment is performed on a portion of the dielectric layer that is covered with a column constituting the inorganic alignment film.   The liquid crystal display device according to claim 3, wherein a surface treatment is performed on a surface of the column. A method of manufacturing a liquid crystal display device comprising a pair of substrates that sandwich a liquid crystal layer,
Forming at least one of the pair of substrates,
A dielectric layer forming step of forming a dielectric layer containing SiO ₂ on the substrate;
An alignment film forming step of forming an inorganic alignment film for controlling the alignment of liquid crystal molecules constituting the liquid crystal layer on the dielectric layer by oblique deposition;
A surface treatment step of treating the surface of the dielectric layer with a silane compound;
A manufacturing method comprising:   The manufacturing method according to claim 5, wherein the surface treatment step is performed after the alignment film forming step. The silane compound has the general formula (1)

[Wherein n is 1 or 2, and m is an integer of 6 to 18]
It is represented by these, The manufacturing method of Claim 6 characterized by the above-mentioned.   The manufacturing method according to claim 5, wherein the surface treatment step is performed before the alignment film forming step. The silane compound has the general formula (2)

[Wherein n is 1 or 2, and m is an integer of 6 to 18]
It is represented by these, The manufacturing method of Claim 8 characterized by the above-mentioned.   The method according to claim 8 or 9, wherein the surface of the inorganic alignment film is surface-treated with a silane compound after the alignment film forming step.   The manufacturing method according to claim 5, wherein in the dielectric layer forming step, the dielectric layer is formed by a plasma CVD method using tetraethoxysilane as a source gas.   A projection display device comprising the liquid crystal display device according to claim 1.

Images